An X-PON system, such as a Gigabit capability Passive Optical Network (Gigabit capability Passive Optical Network, hereinafter referred to as GPON) and an Ethernet Passive Optical Network (Ethernet Passive Optical Network, hereinafter referred to as EPON), is generally formed by an optical network termination (Optical Line Termination, hereinafter referred to as OLT) located in a central office, optical network units (Optical Network Units, hereinafter referred to as ONUs)/optical network terminations (Optical Network Terminations, hereinafter referred to as ONTs) located at a user end, and an optical distribution network (Optical Distribution Network, hereinafter referred to as ODN). The ratio of the number of OLTs in the central office to the number of ONUs at the user end is 1:N. The OLT and the ONUs implement aggregation of the user-end ONUs through optical splitters.
In the XPON system, the OLT in the central office manages authorization of the ONUs in each timeslot, and implements bandwidth management of an uplink ONU. In the prior art, a dynamic bandwidth assignment (Dynamic Bandwidth Assignment, hereinafter referred to as DBA) device implements the function of uplink bandwidth management. The DBA device provides many service bandwidth types for an operator. The DBA device can adjust the bandwidth between the ONUs dynamically according to service traffic requirements of the ONUs and service bandwidth configurations of the ONUs. The DBA device performs bandwidth management based on a transmission container (Transmission Container, hereinafter referred to as TCONT) as a unit. The TCONT serves as a transmission carrier of a service, and all services are transmitted and performed on the TCONT. In the prior art, the DBA device implements the bandwidth management through the following three modules: a collection module, configured to collect TCONT information reported by the TCONT; an assignment module, configured to perform bandwidth calculation and assignment on the collected TCONT information according to a bandwidth priority; and a delivery module, configured to deliver a corresponding assigned bandwidth to an ONU in light of ONU information. Working cycles of the collection module, the assignment module, and the delivery module are the same, and are equal to a DBA cycle. In a stage when the delivery module performs bandwidth delivery, for all TCONT bandwidths, a configured delivery cycle is fixed and constant no matter whether the granularity of the bandwidth is coarse or fine. The delivery cycle is less than or equal to the DBA cycle.
During the implementation of the present invention, the prior art has the following disadvantages: In the prior art, in the stage when the delivery module of the DBA device performs bandwidth delivery, the delivery cycles of all the TCONT bandwidths are fixed, and the delivery cycle is unchangeable in the delivery stage, which lead to a low utilization of the delivered bandwidth and a low data transmission efficiency.